arch/arm64/crypto/crc32-arm64.c - kernel/bruno - Git at Google

 /*
  * crc32-arm64.c - CRC32 and CRC32C using optional ARMv8 instructions
  *
  * Module based on crypto/crc32c_generic.c
  *
  * CRC32 loop taken from Ed Nevill's Hadoop CRC patch
  * http://mail-archives.apache.org/mod_mbox/hadoop-common-dev/201406.mbox/%3C1403687030.3355.19.camel%40localhost.localdomain%3E
  *
  * Using inline assembly instead of intrinsics in order to be backwards
  * compatible with older compilers.
  *
  * Copyright (C) 2014 Linaro Ltd <yazen.ghannam@linaro.org>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
  * published by the Free Software Foundation.
  */

 #include <linux/unaligned/access_ok.h>
 #include <linux/cpufeature.h>
 #include <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/string.h>

 #include <crypto/internal/hash.h>

 MODULE_AUTHOR("Yazen Ghannam <yazen.ghannam@linaro.org>");
 MODULE_DESCRIPTION("CRC32 and CRC32C using optional ARMv8 instructions");
 MODULE_LICENSE("GPL v2");

 #define CRC32X(crc, value) __asm__("crc32x %w[c], %w[c], %x[v]":[c]"+r"(crc):[v]"r"(value))
 #define CRC32W(crc, value) __asm__("crc32w %w[c], %w[c], %w[v]":[c]"+r"(crc):[v]"r"(value))
 #define CRC32H(crc, value) __asm__("crc32h %w[c], %w[c], %w[v]":[c]"+r"(crc):[v]"r"(value))
 #define CRC32B(crc, value) __asm__("crc32b %w[c], %w[c], %w[v]":[c]"+r"(crc):[v]"r"(value))
 #define CRC32CX(crc, value) __asm__("crc32cx %w[c], %w[c], %x[v]":[c]"+r"(crc):[v]"r"(value))
 #define CRC32CW(crc, value) __asm__("crc32cw %w[c], %w[c], %w[v]":[c]"+r"(crc):[v]"r"(value))
 #define CRC32CH(crc, value) __asm__("crc32ch %w[c], %w[c], %w[v]":[c]"+r"(crc):[v]"r"(value))
 #define CRC32CB(crc, value) __asm__("crc32cb %w[c], %w[c], %w[v]":[c]"+r"(crc):[v]"r"(value))

 static u32 crc32_arm64_le_hw(u32 crc, const u8 *p, unsigned int len)
 {
 	s64 length = len;

 	while ((length -= sizeof(u64)) >= 0) {
 		CRC32X(crc, get_unaligned_le64(p));
 		p += sizeof(u64);
 	}

 	/* The following is more efficient than the straight loop */
 	if (length & sizeof(u32)) {
 		CRC32W(crc, get_unaligned_le32(p));
 		p += sizeof(u32);
 	}
 	if (length & sizeof(u16)) {
 		CRC32H(crc, get_unaligned_le16(p));
 		p += sizeof(u16);
 	}
 	if (length & sizeof(u8))
 		CRC32B(crc, *p);

 	return crc;
 }

 static u32 crc32c_arm64_le_hw(u32 crc, const u8 *p, unsigned int len)
 {
 	s64 length = len;

 	while ((length -= sizeof(u64)) >= 0) {
 		CRC32CX(crc, get_unaligned_le64(p));
 		p += sizeof(u64);
 	}

 	/* The following is more efficient than the straight loop */
 	if (length & sizeof(u32)) {
 		CRC32CW(crc, get_unaligned_le32(p));
 		p += sizeof(u32);
 	}
 	if (length & sizeof(u16)) {
 		CRC32CH(crc, get_unaligned_le16(p));
 		p += sizeof(u16);
 	}
 	if (length & sizeof(u8))
 		CRC32CB(crc, *p);

 	return crc;
 }

 #define CHKSUM_BLOCK_SIZE	1
 #define CHKSUM_DIGEST_SIZE	4

 struct chksum_ctx {
 	u32 key;
 };

 struct chksum_desc_ctx {
 	u32 crc;
 };

 static int chksum_init(struct shash_desc *desc)
 {
 	struct chksum_ctx *mctx = crypto_shash_ctx(desc->tfm);
 	struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);

 	ctx->crc = mctx->key;

 	return 0;
 }

 /*
  * Setting the seed allows arbitrary accumulators and flexible XOR policy
  * If your algorithm starts with ~0, then XOR with ~0 before you set
  * the seed.
  */
 static int chksum_setkey(struct crypto_shash *tfm, const u8 *key,
 			 unsigned int keylen)
 {
 	struct chksum_ctx *mctx = crypto_shash_ctx(tfm);

 	if (keylen != sizeof(mctx->key)) {
 		crypto_shash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
 		return -EINVAL;
 	}
 	mctx->key = get_unaligned_le32(key);
 	return 0;
 }

 static int chksum_update(struct shash_desc *desc, const u8 *data,
 			 unsigned int length)
 {
 	struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);

 	ctx->crc = crc32_arm64_le_hw(ctx->crc, data, length);
 	return 0;
 }

 static int chksumc_update(struct shash_desc *desc, const u8 *data,
 			 unsigned int length)
 {
 	struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);

 	ctx->crc = crc32c_arm64_le_hw(ctx->crc, data, length);
 	return 0;
 }

 static int chksum_final(struct shash_desc *desc, u8 *out)
 {
 	struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);

 	put_unaligned_le32(ctx->crc, out);
 	return 0;
 }

 static int chksumc_final(struct shash_desc *desc, u8 *out)
 {
 	struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);

 	put_unaligned_le32(~ctx->crc, out);
 	return 0;
 }

 static int __chksum_finup(u32 crc, const u8 *data, unsigned int len, u8 *out)
 {
 	put_unaligned_le32(crc32_arm64_le_hw(crc, data, len), out);
 	return 0;
 }

 static int __chksumc_finup(u32 crc, const u8 *data, unsigned int len, u8 *out)
 {
 	put_unaligned_le32(~crc32c_arm64_le_hw(crc, data, len), out);
 	return 0;
 }

 static int chksum_finup(struct shash_desc *desc, const u8 *data,
 			unsigned int len, u8 *out)
 {
 	struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);

 	return __chksum_finup(ctx->crc, data, len, out);
 }

 static int chksumc_finup(struct shash_desc *desc, const u8 *data,
 			unsigned int len, u8 *out)
 {
 	struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);

 	return __chksumc_finup(ctx->crc, data, len, out);
 }

 static int chksum_digest(struct shash_desc *desc, const u8 *data,
 			 unsigned int length, u8 *out)
 {
 	struct chksum_ctx *mctx = crypto_shash_ctx(desc->tfm);

 	return __chksum_finup(mctx->key, data, length, out);
 }

 static int chksumc_digest(struct shash_desc *desc, const u8 *data,
 			 unsigned int length, u8 *out)
 {
 	struct chksum_ctx *mctx = crypto_shash_ctx(desc->tfm);

 	return __chksumc_finup(mctx->key, data, length, out);
 }

 static int crc32_cra_init(struct crypto_tfm *tfm)
 {
 	struct chksum_ctx *mctx = crypto_tfm_ctx(tfm);

 	mctx->key = 0;
 	return 0;
 }

 static int crc32c_cra_init(struct crypto_tfm *tfm)
 {
 	struct chksum_ctx *mctx = crypto_tfm_ctx(tfm);

 	mctx->key = ~0;
 	return 0;
 }

 static struct shash_alg crc32_alg = {
 	.digestsize		=	CHKSUM_DIGEST_SIZE,
 	.setkey			=	chksum_setkey,
 	.init			=	chksum_init,
 	.update			=	chksum_update,
 	.final			=	chksum_final,
 	.finup			=	chksum_finup,
 	.digest			=	chksum_digest,
 	.descsize		=	sizeof(struct chksum_desc_ctx),
 	.base			=	{
 		.cra_name		=	"crc32",
 		.cra_driver_name	=	"crc32-arm64-hw",
 		.cra_priority		=	300,
 		.cra_blocksize		=	CHKSUM_BLOCK_SIZE,
 		.cra_alignmask		=	0,
 		.cra_ctxsize		=	sizeof(struct chksum_ctx),
 		.cra_module		=	THIS_MODULE,
 		.cra_init		=	crc32_cra_init,
 	}
 };

 static struct shash_alg crc32c_alg = {
 	.digestsize		=	CHKSUM_DIGEST_SIZE,
 	.setkey			=	chksum_setkey,
 	.init			=	chksum_init,
 	.update			=	chksumc_update,
 	.final			=	chksumc_final,
 	.finup			=	chksumc_finup,
 	.digest			=	chksumc_digest,
 	.descsize		=	sizeof(struct chksum_desc_ctx),
 	.base			=	{
 		.cra_name		=	"crc32c",
 		.cra_driver_name	=	"crc32c-arm64-hw",
 		.cra_priority		=	300,
 		.cra_blocksize		=	CHKSUM_BLOCK_SIZE,
 		.cra_alignmask		=	0,
 		.cra_ctxsize		=	sizeof(struct chksum_ctx),
 		.cra_module		=	THIS_MODULE,
 		.cra_init		=	crc32c_cra_init,
 	}
 };

 static int __init crc32_mod_init(void)
 {
 	int err;

 	err = crypto_register_shash(&crc32_alg);

 	if (err)
 		return err;

 	err = crypto_register_shash(&crc32c_alg);

 	if (err) {
 		crypto_unregister_shash(&crc32_alg);
 		return err;
 	}

 	return 0;
 }

 static void __exit crc32_mod_exit(void)
 {
 	crypto_unregister_shash(&crc32_alg);
 	crypto_unregister_shash(&crc32c_alg);
 }

 module_cpu_feature_match(CRC32, crc32_mod_init);
 module_exit(crc32_mod_exit);
	/*
	* crc32-arm64.c - CRC32 and CRC32C using optional ARMv8 instructions
	*
	* Module based on crypto/crc32c_generic.c
	*
	* CRC32 loop taken from Ed Nevill's Hadoop CRC patch
	* http://mail-archives.apache.org/mod_mbox/hadoop-common-dev/201406.mbox/%3C1403687030.3355.19.camel%40localhost.localdomain%3E
	*
	* Using inline assembly instead of intrinsics in order to be backwards
	* compatible with older compilers.
	*
	* Copyright (C) 2014 Linaro Ltd <yazen.ghannam@linaro.org>
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License version 2 as
	* published by the Free Software Foundation.
	*/

	#include <linux/unaligned/access_ok.h>
	#include <linux/cpufeature.h>
	#include <linux/init.h>
	#include <linux/kernel.h>
	#include <linux/module.h>
	#include <linux/string.h>

	#include <crypto/internal/hash.h>

	MODULE_AUTHOR("Yazen Ghannam <yazen.ghannam@linaro.org>");
	MODULE_DESCRIPTION("CRC32 and CRC32C using optional ARMv8 instructions");
	MODULE_LICENSE("GPL v2");

	#define CRC32X(crc, value) __asm__("crc32x %w[c], %w[c], %x[v]":[c]"+r"(crc):[v]"r"(value))
	#define CRC32W(crc, value) __asm__("crc32w %w[c], %w[c], %w[v]":[c]"+r"(crc):[v]"r"(value))
	#define CRC32H(crc, value) __asm__("crc32h %w[c], %w[c], %w[v]":[c]"+r"(crc):[v]"r"(value))
	#define CRC32B(crc, value) __asm__("crc32b %w[c], %w[c], %w[v]":[c]"+r"(crc):[v]"r"(value))
	#define CRC32CX(crc, value) __asm__("crc32cx %w[c], %w[c], %x[v]":[c]"+r"(crc):[v]"r"(value))
	#define CRC32CW(crc, value) __asm__("crc32cw %w[c], %w[c], %w[v]":[c]"+r"(crc):[v]"r"(value))
	#define CRC32CH(crc, value) __asm__("crc32ch %w[c], %w[c], %w[v]":[c]"+r"(crc):[v]"r"(value))
	#define CRC32CB(crc, value) __asm__("crc32cb %w[c], %w[c], %w[v]":[c]"+r"(crc):[v]"r"(value))

	static u32 crc32_arm64_le_hw(u32 crc, const u8 *p, unsigned int len)
	{
	s64 length = len;

	while ((length -= sizeof(u64)) >= 0) {
	CRC32X(crc, get_unaligned_le64(p));
	p += sizeof(u64);
	}

	/* The following is more efficient than the straight loop */
	if (length & sizeof(u32)) {
	CRC32W(crc, get_unaligned_le32(p));
	p += sizeof(u32);
	}
	if (length & sizeof(u16)) {
	CRC32H(crc, get_unaligned_le16(p));
	p += sizeof(u16);
	}
	if (length & sizeof(u8))
	CRC32B(crc, *p);

	return crc;
	}

	static u32 crc32c_arm64_le_hw(u32 crc, const u8 *p, unsigned int len)
	{
	s64 length = len;

	while ((length -= sizeof(u64)) >= 0) {
	CRC32CX(crc, get_unaligned_le64(p));
	p += sizeof(u64);
	}

	/* The following is more efficient than the straight loop */
	if (length & sizeof(u32)) {
	CRC32CW(crc, get_unaligned_le32(p));
	p += sizeof(u32);
	}
	if (length & sizeof(u16)) {
	CRC32CH(crc, get_unaligned_le16(p));
	p += sizeof(u16);
	}
	if (length & sizeof(u8))
	CRC32CB(crc, *p);

	return crc;
	}

	#define CHKSUM_BLOCK_SIZE 1
	#define CHKSUM_DIGEST_SIZE 4

	struct chksum_ctx {
	u32 key;
	};

	struct chksum_desc_ctx {
	u32 crc;
	};

	static int chksum_init(struct shash_desc *desc)
	{
	struct chksum_ctx *mctx = crypto_shash_ctx(desc->tfm);
	struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);

	ctx->crc = mctx->key;

	return 0;
	}

	/*
	* Setting the seed allows arbitrary accumulators and flexible XOR policy
	* If your algorithm starts with ~0, then XOR with ~0 before you set
	* the seed.
	*/
	static int chksum_setkey(struct crypto_shash tfm, const u8 key,
	unsigned int keylen)
	{
	struct chksum_ctx *mctx = crypto_shash_ctx(tfm);

	if (keylen != sizeof(mctx->key)) {
	crypto_shash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
	return -EINVAL;
	}
	mctx->key = get_unaligned_le32(key);
	return 0;
	}

	static int chksum_update(struct shash_desc desc, const u8 data,
	unsigned int length)
	{
	struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);

	ctx->crc = crc32_arm64_le_hw(ctx->crc, data, length);
	return 0;
	}

	static int chksumc_update(struct shash_desc desc, const u8 data,
	unsigned int length)
	{
	struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);

	ctx->crc = crc32c_arm64_le_hw(ctx->crc, data, length);
	return 0;
	}

	static int chksum_final(struct shash_desc desc, u8 out)
	{
	struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);

	put_unaligned_le32(ctx->crc, out);
	return 0;
	}

	static int chksumc_final(struct shash_desc desc, u8 out)
	{
	struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);

	put_unaligned_le32(~ctx->crc, out);
	return 0;
	}

	static int __chksum_finup(u32 crc, const u8 data, unsigned int len, u8 out)
	{
	put_unaligned_le32(crc32_arm64_le_hw(crc, data, len), out);
	return 0;
	}

	static int __chksumc_finup(u32 crc, const u8 data, unsigned int len, u8 out)
	{
	put_unaligned_le32(~crc32c_arm64_le_hw(crc, data, len), out);
	return 0;
	}

	static int chksum_finup(struct shash_desc desc, const u8 data,
	unsigned int len, u8 *out)
	{
	struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);

	return __chksum_finup(ctx->crc, data, len, out);
	}

	static int chksumc_finup(struct shash_desc desc, const u8 data,
	unsigned int len, u8 *out)
	{
	struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);

	return __chksumc_finup(ctx->crc, data, len, out);
	}

	static int chksum_digest(struct shash_desc desc, const u8 data,
	unsigned int length, u8 *out)
	{
	struct chksum_ctx *mctx = crypto_shash_ctx(desc->tfm);

	return __chksum_finup(mctx->key, data, length, out);
	}

	static int chksumc_digest(struct shash_desc desc, const u8 data,
	unsigned int length, u8 *out)
	{
	struct chksum_ctx *mctx = crypto_shash_ctx(desc->tfm);

	return __chksumc_finup(mctx->key, data, length, out);
	}

	static int crc32_cra_init(struct crypto_tfm *tfm)
	{
	struct chksum_ctx *mctx = crypto_tfm_ctx(tfm);

	mctx->key = 0;
	return 0;
	}

	static int crc32c_cra_init(struct crypto_tfm *tfm)
	{
	struct chksum_ctx *mctx = crypto_tfm_ctx(tfm);

	mctx->key = ~0;
	return 0;
	}

	static struct shash_alg crc32_alg = {
	.digestsize = CHKSUM_DIGEST_SIZE,
	.setkey = chksum_setkey,
	.init = chksum_init,
	.update = chksum_update,
	.final = chksum_final,
	.finup = chksum_finup,
	.digest = chksum_digest,
	.descsize = sizeof(struct chksum_desc_ctx),
	.base = {
	.cra_name = "crc32",
	.cra_driver_name = "crc32-arm64-hw",
	.cra_priority = 300,
	.cra_blocksize = CHKSUM_BLOCK_SIZE,
	.cra_alignmask = 0,
	.cra_ctxsize = sizeof(struct chksum_ctx),
	.cra_module = THIS_MODULE,
	.cra_init = crc32_cra_init,
	}
	};

	static struct shash_alg crc32c_alg = {
	.digestsize = CHKSUM_DIGEST_SIZE,
	.setkey = chksum_setkey,
	.init = chksum_init,
	.update = chksumc_update,
	.final = chksumc_final,
	.finup = chksumc_finup,
	.digest = chksumc_digest,
	.descsize = sizeof(struct chksum_desc_ctx),
	.base = {
	.cra_name = "crc32c",
	.cra_driver_name = "crc32c-arm64-hw",
	.cra_priority = 300,
	.cra_blocksize = CHKSUM_BLOCK_SIZE,
	.cra_alignmask = 0,
	.cra_ctxsize = sizeof(struct chksum_ctx),
	.cra_module = THIS_MODULE,
	.cra_init = crc32c_cra_init,
	}
	};

	static int __init crc32_mod_init(void)
	{
	int err;

	err = crypto_register_shash(&crc32_alg);

	if (err)
	return err;

	err = crypto_register_shash(&crc32c_alg);

	if (err) {
	crypto_unregister_shash(&crc32_alg);
	return err;
	}

	return 0;
	}

	static void __exit crc32_mod_exit(void)
	{
	crypto_unregister_shash(&crc32_alg);
	crypto_unregister_shash(&crc32c_alg);
	}

	module_cpu_feature_match(CRC32, crc32_mod_init);
	module_exit(crc32_mod_exit);